Vehicle lifting jack



May 5, 1931. c. sTUKENBoRG VEHICLE LIFTING JACK Filed Jan. 50, 1928 l0 05 Q/ l/ a 2 2 /M /7 f 5 /Ls wr. Y 7 la Mu .6/ 7 P/ 4:5 7u .2 0 NZ @c [y0 2 2 2 M fw 5 a M W 2J nl o@ j 2T l.

M 24 W ff f /wa/ 4 #a C w e w, 2 W. `I A "i: /f 1v vPatterned May 5,.1931 UNITED STATES PATENT oE'FlcE LOUIS G'. STUKENBORG, OF MEMPIS,TENNESSEE, ASSIGNOR TO OILDRULIC LIFT COMPANY, OF MEMPHIS, TENNESSEE, ACORPORATION OF DELAWARE VEHICLE LIFTING JACK I Application led January30, 1928. Serial No. 250,468. R E l U This invention relates to animproved fluid pressure actuated lifting jack and has especial relationto the piston or ram and the fluid actuating and control meansassociatedtheref l i Among the objects of my invention is to provide an improvedram in which all the moving and actuating parts are assembled in 'asingle compa-ct unit.

The means by which the foregoing and other objects are accomplished andthe manner of their accomplishment will readily be understood from thefollowing specification on reference to the accompanying drawings inwhich:

Fig.` 1 is asectional elevation taken on the approximate center line ofthe cylinder and piston, showing the preferred form of control.

Fig. 2 is a similar elevation of the lower end of the cylinder andpiston showing a minor modification in the pump mounting thereof.

Fig. 3 is a sectional elevation of the upper end of the piston taken atright angles to the view shown in Fig. 1. v

Referring now to the drawings in which the various parts are indicatedby numerals, 10 is a vertical cylinder having a closed bottom 11 andprovided intermediate its height with a guiding ring 12 and near theupper end with a guiding ring 13 forming also the lower portion of astuffing box, which stuffing box is provided with suitable packing 14,held in place by a packing gland 15. Disposed within the cylinder 10 isa hollow piston or ram 16 to the upper end of which a lifting head 17 ofany desired form may be secured. The lower end of the hollow piston isclosed by m a head 18 and the piston is utilized as a reservoir in whichthe lifting fluid, preferably oil is carred.

19 is a pump secured to the head 18 either, as shown in Fig. 1, to theunder side there- 45 of, or as shown in Fig. 2 to the upper side,

which pump is provided with an inlet v20 directly connected to theinterior ofthe piston 16, and with an outlet 21 leading' from the pumpto the interior of the cylinder 10outside the piston 16. l

In the 'form shown in Fig. 1 the ump is preferably provided with athreaded ange 22 which may be secured directly into the head 18 of thepiston and in such case the pump inlet is preferably led directlythrough this flange as is indicated in that view. i

23 is vthe pump shaft, which is preferably provided with a sleeve 24pinned thereto into which sleeve the squared lower end 25 of the motorsha-ft 26 may be slipped. 27 indicates an electric motor used fordriving the pump. This motor is disposed entirely within the piston 16so that preferably no portion thereof extends above the upper end of thepiston 16. 28 are bosses extending laterally on opposite sides of themotor, into which bosses cap screws 29 may be secured, to support themotor within the piston 16.

30 is an angle valve, the inlet 31 from which may be secured through asuitable hole tapped through the bottom 18 of the piston, which valveforms a bleeder to allow the return of the fluid from the cylinder tothe interior ofl the piston. From this valve, a control stem 32 leads tothe upper end of the piston. Preferably this stem is connected to thestem of the valve 30 by a sleeve 33 similar to the sleeve 24 beforedescribed. The upper end of the stem 32 may be provided with a bevelgear vthe valve from an exterior point.

If desired, a check valve 37 may be used to prevent return flow of thefluid through the pump. Should it be desired a continuation 38 of thepiston may be carried below the head 18 to form a stop for the piston inits descent and to thereby protect the pump.

The chamber or pocket. thus formed also serves to trap air which may becarried into the cylinder when the piston is beingfraised and to holdsame in convenient proximity to the release valve, so that such air on.the descent of the piston is carried into the piston reservoir andthere released.

In order to limit the vertical lift of theI piston, only such amount ofHuid is placed therein as will, when completely used raise the piston tothe desired height, so that the amount which the piston will lift, willthereby `be automatically regulated without mechanical stops of anykind, whether the pump and motor be cut off at the proper time or not.

By associating the pump and motor with the piston and especially byplacing the pump at the point of discharge from the piston into thecylinder the control is greatly simplified and improved. The passagewaysfor the flow of the liquid are reduced in length and angles or elbowsare avoided. In addition the shipping and assembly of the pump isgreatly facilitated and in every way the control improved.

In using the device the cylinder is ordinarily set in the ground withits upper end approximately level with the surface thereof. The pistonassembly is then placed therein and the stuing box gland tightened. Thecylinder may. be then supplied with the proper amount of fluid, themotor wired up in the usual manner and the device is ready for use.

To operate the jack, the bleeder valve is closed, the motor started andallowed to run until all the fluid is pumped from the. piston into thecylinder after which the motor is preferably shut off. The piston willthereafter remain at such level until the bleeder valve is opened and itis again allowed to sink by gravity to its initial position.

Should it be desired to stop the piston in its upward stroke at anydesired point, it is only necessary to shut the motor ofi' when suchposition is reached. Should it be desired to stop the piston in itsdownward motion it is only necessary to close the bleeder valve whensuch position of descent has been reached, as is desired.

It will be understood that the drawing and description herein isillustrative only and that the details herein mentioned may be deviatedfrom except as they may be hereinafter set out in the claims.

Having described my invcntion,lwliat I claim is:

l. In a lifting jack, a vertically ,disposed hollowcylinder, and a selfcontained lifting unit vertically movable therein, said unit comprisinga hollow piston adapted to contain a lifting fluid, and having the lowerend thereof interiorly threaded, a pump having a threaded flangetherearound screwed into said threaded portion to form a closure for thelower end of said piston, an intake for said pump within said piston, anoutlet for said pump exterior of said piston, and means carried by saidpiston for actuating said pump.

2. In a lifting jack, a vertically disposed hollow cylinder, and a selfcontained lifting unit vertically movable therein, said unit comprisinga hollow piston closed at the lower end and adapted to contain a liftingfluid, a vertically disposed centrifugal pump secured within said closedend, and having its shaft centrally aligned by said piston, a inotorcarried by the upper end of said piston and having its shaft positionedby said piston in axial alignment with said pump shaft, and a shaftconnecting said pump and motor shafts.

3. In a lifting jack, a vertically disposed hollow cylinder and a selfcontained lifting unit vertically movable therein, said unit comprisinga hollow piston adapted to contain a lifting fluid and having an openlower end, a pump having a supporting disk arranged to form a closurefor said open lower end of said piston, an intake for said pump withinsaid piston, an outlet for said pump exterior to said ypiston and meanscarried by said piston for actuating said pump.

4. In a lifting jack, a vertically disposed hollow cylinder and a selfcontained lifting unit vertically movable therein, said unit comprisinga tubular piston provided with a closure adjacent but spaced above itslower end and adapted to contain a lifting fluid, a pump carried by thelower end of said piston and having its shaft centrally aligned thereby,said pump having parts projecting below said closure but terminatingabove the lower end of the piston, a motor carried by the upper end ofsaid piston and having its shaft positioned by said piston in axialalignment with said pump shaft and a shaft connecting said pump andmotor shafts.

5. In a lifting jack, a vertically disposed hollow cylinder and a selfcontained lifting unit vertically movable therein, sai unit comprising ahollow piston adapted to contain a lifting fluid and having at its lowerend an inwardly projecting, open center flange, a pump secured to saidflange to form a closure for said open center, an intake for said pumpwithin said piston, an outlet for said pump exterior to said piston andmeans carried by said piston for actuating said pump.

6. A lifting pack kcomprising a vertically disposed hollow cylinder anda self contained lifting unit vertically movable therein, said liftingunit comprising a hollow piston adapted to serve as a reservoir for alifting fluid, a closure for the lower end of said piston, a pump'peripherally within said piston and located below said closure forexerting an upward lift thereon and thereby on the piston, an intake forsaid pump within said piston and an outlet for said pump exterior tosaid piston and within said cylinder.

7. A lifting jack comprising a vertically I disposed hollow cylinder anda self contained lifting unit vertically movable therein, said liftingunit comprising a hollow piston adapted to serve as a lifting fluidreservoir, a partition disposed transversely across said piston adjacentbut above the lower end thereof whereby a chamber is formed below saidpartition, a pump secured to said head within said chamber and havingits lower extremity terminating above the lower end of v the pistonwhereby the pump is housed within said chamber and the lower end of thepiston acts as a lower limit stop to protect the pump from injury, anintake for said pump within said piston, an outlet for said pumpexterior to said piston and within said cyl` inder, a motor carried bysaid piston and operatively connected with said pump and a manuallyoperable releasevalve connecting said chamber and the interior of saidpiston, to control release How between the exterior of said piston andthe interior thereof independent of said pump.

In testimony whereof I hereunto ailix my signature. l

LOUIS C. STUKENBORG.

